Personal cleansing compositions that attempt to provide skin-conditioning benefits are known. Many of these compositions are aqueous systems comprising an emulsified conditioning oil or other similar materials in combination with a lathering surfactant. Although these products provide both conditioning and cleansing benefits, it is often difficult to formulate a product that deposits sufficient amount of skin conditioning agents on skin during use. In order to combat emulsification of the skin conditioning agents by the cleansing surfactant, large amounts of the skin conditioning agent are added to the compositions. However, this introduces another problem associated with these dual cleansing and conditioning products. Raising the level of skin conditioning agent in order to achieve increased deposition negatively affects product stability.
It is known that dispersions and emulsions in personal cleansing compositions that comprise structured surfactants exhibit buoyant forces due to the difference in density between the continuous structured surfactant component, and the benefit component. For example, when the benefit component comprises a hydrophobic material such as a triglyceride or a hydrocarbon material, the density of the dispersed phase is about 0.9 gm/cm3, whereas the density of the continuous structured surfactant component is about 1.0 gm/cm3. When the buoyant force of a benefit component exceeds the local value of the yield stress of the continuous structured surfactant component, the droplet can rise through the continuous phase in a process called creaming. Given a sufficient amount of creaming, exacerbated by coalescence of the benefit component, phase separation can occur as the product becomes unstable, e.g., during shipping and extended storage on a store shelf.
Accordingly, the need still remains for a multi-phase, blended personal cleansing composition that provides both cleansing and improved skin conditioning benefits which remains for a personal cleansing composition comprising two phases in physical contact that remain stable for long periods of time.